1. Field of the Invention
The invention is in the field of image enhancement and more specifically in a system of using polarized focused and defocused images of the same optical scene in real time for background suppression and target image enhancement.
2. Description of the Prior Art
In virtually all forward looking infrared imagers (FLIRS) or visible spectrum imagers, a detector array is scanned across the thermal image, allowing the background to be suppressed by a.c. coupling of the detectors. Interest is presently increasing in the concept of a staring, i.e. non-scanning, imager because of the reduction of moving parts and the increased potential sensitivity afforded by the larger number of detectors that may be used. It is in the staring imagers that low contrast becomes an important limitation, many instances occur where a scene is made up of many high spatial frequency targets and overall uniform low spatial frequency background. This is true of IR and visible light scenes in the presence of fog, smoke, or haze. In scenes of this type, the limits of observation are usually set by the low contrast. The present invention helps solve the low constrast problem.